Chris,
I ordered the DL-90 directly from race-technology. It was shipped to me from
cb racing . Race-technology didmention on their website that the $650 price was an introductory price good till the end of 2002 (cb racing still lists the DL-90 at $650), but
D2 Engineering now lists the DL 90 at $800.
I have played around with the unit in my daily driver and am really amazed at the accuracy it records to. For example I did some laps of a large parking lot near me, and varied the line incrementaly, (changing radius and diameter of turns). When I used the "overlay lap" function it actually showed the variances in line. I did my laps at speed less than 40 mph in my mountaineer so it was really easy to be consitent with the line and the changes were controlled.
ramble mode off
Also check the D2 schedule, they will be at gingerman in april with DL-90 rentals. (you do run gingerman?)